Array drive replacement issue

[StatMatt]

I had an array data drive that dropped out of the array for some reason. It's an older 8tb SMR drive and I didn't completely trust it, so I decided to replace it with a new 14tb non-SMR drive.  I followed the steps listed here: https://forums.unraid.net/forum/55-general-support/, although I'm not completely sure I remember any checkbox.  Anyway, the machine chugged away for 24+ hours updating parity, but now the new drive is showing as "Unmountable: Unsupported or no filesystem".  It's giving me a checkbox to format the drive, but it doesn't seem like I would want to format the drive after the parity has been rebuilt, right?  Did I screw something up?

unsmedley-diagnostics-20231027-1902.zip

[JorgeB]

Check filesystem on disk3, run it without -n.

[itimpi]

8 hours ago, StatMatt said:

Anyway, the machine chugged away for 24+ hours updating parity, but now the new drive is showing as "Unmountable: Unsupported or no filesystem".

Did the drive show as unmountable before you started the rebuild?    Just asking as a rebuild will not clear that state and it is normally better to try to clear the unmountable state before doing the rebuild.

 

8 hours ago, StatMatt said:

after the parity has been rebuilt, right? 

Just to clarify - it is not parity that is being rebuilt, but the 'failed' disk is being rebuilt using parity plus the other data drives.

[StatMatt]

7 hours ago, JorgeB said:

Check filesystem on disk3, run it without -n.

Thanks for this tip. I did with the -v option. It generated a TON of output of things that looked alarming, but there wasn't any clear way to copy that log to a file from the GUI so I don't remember what it said. Went back to Main, stopped the array (because it had been in maintenance mode), restarted it, and everything seems okay.(?)

 

6 hours ago, itimpi said:

Did the drive show as unmountable before you started the rebuild?    Just asking as a rebuild will not clear that state and it is normally better to try to clear the unmountable state before doing the rebuild.

 

Just to clarify - it is not parity that is being rebuilt, but the 'failed' disk is being rebuilt using parity plus the other data drives.

Sorry, but I don't remember if it said that or not.  If it did, I wouldn't have thought that weird because it was a brand new drive.  Seems like it SHOULD be unmountable!  The instructions (https://docs.unraid.net/legacy/FAQ/replacing-a-data-drive/) didn't say anything about formatting the drive or making it mountable or whatever - I just assumed that would get handled though the rebuild process.

 

 

Just a comment: I've been using UnRAID for about a year and a half now, and this is the second time I've had a problem replacing an array drive.  For most of users, I suspect replacing a drive is not an everyday occurrence.  It would be super helpful if there were a "wizard" or something to walk us through the steps, because the documentation isn't great (doesn't it seem like something is missing between step 8 and 9? And to itimpi's comment how would I know that the if the drive is showing unmountable I'm supposed to do something else first?) and it seems like there are several "gotchas" that make the process fragile.  Granted it seems like it's been fixed now, but I have NO idea what I did wrong, nor will I remember the details the next time an issue comes up.  Thanks.

[itimpi]

Just now, StatMatt said:

Sorry, but I don't remember if it said that or not.  If it did, I wouldn't have thought that weird because it was a brand new drive.  Seems like it SHOULD be unmountable!

Actually no as this is the status of the 'emulated' drive - not the replacement drive.    The rebuild process overwrites every sector on the replacement drive and reinstates the file system of the emulated drive on the replacement drive so whether it is formatted or not before you begin is irrelevant.

[StatMatt]

2 minutes ago, itimpi said:

Actually no as this is the status of the 'emulated' drive - not the replacement drive.    The rebuild process overwrites every sector on the replacement drive and reinstates the file system of the emulated drive on the replacement drive so whether it is formatted or not before you begin is irrelevant.

I have no doubt that what you're saying makes perfect sense to you as someone who does this everyday, but it makes almost no sense to me. I mean, I can understand the words you're using and what they mean, but I'm trying to figure out how a regular user would have any idea that the status for what looks like a physical disk is the actually the status for an emulated drive (assuming they even know there is such a thing as an emulated drive).  Is there some obvious indicator that I overlooked?  Even if I did know that, how would I have known there was anything I was supposed to do about it other than what I did?  I had an old drive suddenly show up as "unmountable", so I replaced it.

 

I'm not trying to be confrontational. I'm just offering feedback that I think could improve UnRAID as a product.  Right now it seems like there are a number of things that are built in ways that apparently make sense to the devs (or ?) but don't make sense to users like me.

[itimpi]

54 minutes ago, StatMatt said:

I had an old drive suddenly show up as "unmountable", so I replaced it.

 

I'm not trying to be confrontational. I'm just offering feedback that I think could improve UnRAID as a product.  Right now it seems like there are a number of things that are built in ways that apparently make sense to the devs (or ?) but don't make sense to users like me.

 

I have requested that Limetech set the word 'unmountable' in a post to be a link to the part of the online documentation that describes how to handle this.   I think that might help users with finding out how best to handle this.

 

There have also been some requests for small visual changes to the GUI to make some of this a bit clearer, although how hard they might be to implement I have no idea.  Since the GUI code is open-source maybe some user might step in and work on this.